Computation Assisted Materials Development for Improved Corrosion Resistance: Session I
Program Organizers: Rishi Pillai, Oak Ridge National Laboratory; Laurence Marks, Northwestern University
Tuesday 8:00 AM
October 11, 2022
Room: 334
Location: David L. Lawrence Convention Center
Session Chair: Rishi Pillai, ORNL; Laurence Marks, Northwestern University
8:00 AM Introductory Comments
8:10 AM Keynote
Computational Approaches to Designing and Predicting the High-Temperature Oxidation Behavior of Alloys: Brian Gleeson1; 1University of Pittsburgh
Development and selection of cost-effective advanced materials are key enablers for emerging clean energy technologies. Many of these applications require structural alloys to withstand extreme corrosive and oxidizing environments for thousands of hours and, in turn, rely on the formation – and reformation – of a protective oxide scale. This presentation will review current and past research aimed at improving the design and predictability of oxidation behavior through computational approaches. Particular focus will be directed at the use of CALPHAD.
8:50 AM Cancelled
Solute Effects on High Temperature Oxidation of Graphitic Cast Iron in Automotive Environments: Christopher Taylor1; Ngan Huynh1; 1The Ohio State University
Molecular dynamics simulations and density functional theory calculations were performed to study the influence of solute elements on the formation of graphitic phases from the melt during cast iron solidification, and on the reactivity and integrity of oxide scales formed during oxidation in exhaust gas environments. The calculations highlight the different roles solute elements can play on relative reactivity towards the different species present in automotive exhaust, as well as on the growth and morphological differentiation of flake vs spheroidal graphite. Graphite morphology can be significant to oxidation performance as it can play a role in the diffusion of oxygen into the alloy as well as nucleating cracks for corrosion fatigue. The impact of solute elements on the work of separation between graphite planes and the cast iron is also presented.
9:10 AM
Oxidation Lifetime Modeling of FeCr and NiCr Foils in Hydrogen-fired Microturbines: Marie Romedenne1; Rishi Pillai1; Bruce Pint1; 1Oak Ridge National Laboratory
Materials degradation models are needed to accelerate the development of materials for a future with hydrogen-fired power generation technologies while limiting their cost. By combining these models with long-term experimental data, a better scientific understanding of the degradation mechanisms and highly accurate predictions can be achieved. In the present work, foil specimens of various Fe- and Ni-based alloys were oxidized in air + 10 % H2O and air + 60 % H2O for up to 5,000 h at 700 °C to simulate the exhaust atmosphere of a hydrogen-fueled microturbine. The impact of composition and water vapor content on the oxidation/ volatilization induced loss of wall thickness will be evaluated with a coupled thermodynamic-kinetic lifetime model. This research was sponsored by the U. S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Combined Heat and Power Program.
9:30 AM
A PRISMS-PF Based Application for Simulating Microgalvanic/Galvanic Corrosion in Alloys: Vishwas Goel1; Yanjun Lyu1; David Montiel1; Katsuyo Thornton1; 1University of Michigan
In this presentation, we will discuss the features and capabilities of a corrosion application developed within the PRISMS-PF framework for simulating microgalvanic and galvanic corrosion in alloys. PRISMS-PF is an open-source phase-field modeling framework that can solve coupled partial differential equations and employs a matrix-free variant of the finite element method with adaptive mesh refinement and explicit time-stepping. In the application, we consider physical phenomena such as migration of ions in the electrolyte, electrochemical reaction at the metal-electrolyte interface, and displacement of the metal-electrolyte interface due to corrosion. To simulate the interfacial motion, the Cahn-Hilliard equation is modified with an interfacial source term proportional to the velocity. The application is well suited for both 2D and 3D systems and exhibits superlinear parallel performance for a sufficiently large system. To demonstrate its utility, we will present the effect of microstructure and material properties on the corrosion rate in Mg-alloys.
9:50 AM
Water-Metal Interactions: Insights from Atomistic Simulations: Susan Sinnott1; 1Pennsylvania State University
The chemical interaction of water with metal surfaces and clusters is of technological importance for applications including energy storage and electrocatalysis. Here, insights into these interactions and the way in which they are impacted by surface structure and composition, as well as cluster size and shape, are provided from classical molecular dynamics simulations using the third-generation charge-optimized many body (COMB3) potentials. These potentials are physics-based and allow for the investigation of heterogeneous interfaces with dynamic charges. In particular, the way in which chemical changes to Pt and Cu surfaces impacts water absorption is examined and the role of chemisorbed O and OH on the kinetics of droplet spreading discussed. In addition, the influence of chemical changes to the surfaces of Pt nanoparticles on their dissolution in water is investigated. The way in which nanoparticle size, coupled with the presence of chemisorbed species, influences nanoparticle dissolution is discussed.
10:10 AM Break
10:30 AM
The Effect of Solute Capture on Chlorine Chemisorption: John Cavin1; James Rondinelli1; 1Northwestern University
Attack from aqueous Cl- can threaten the stability of passivating oxides through several mechanisms including by facilitating the runaway growth of physical perturbations and by causing morphological instabilities through the electromechanical coupling of local electric fields. Here, we present our first principles work on the corrosion resistance of non-equilibrium oxides in the context of Cl- chemisorption, where non-equilibrium oxides are formed on alloy surfaces from solute capture. This mechanism allows cation compositions in the oxide to exceed their nominal equilibrium solubility limits. Using Ni-Cr alloys as a use case, we perform density functional theory calculations to show that rock salt (111) NiO surfaces with Cr replacing Ni in the first metal sublayer resists Cl- chemisorption better than pure NiO and pure Cr2O3. We also present results involving non-equilibrium oxides comprising Mo and W in NiO as well as corundum Cr2O3 with captured Ni to formulate structure-composition and chloride-resistance principles.
10:50 AM
Predicting Hydrogen Diffusivity in Amorphous Titania Using Markov Chain Kinetic Monte Carlo Simulations: James Chapman1; Kyoung Kweon1; Nir Goldman1; Nathan Keilbart1; Tae Heo1; Brandon Wood1; 1Lawrence Livermore National Laboratory
Understanding hydrogen transport is vital to industries focused on discovering new materials for corrosion mitigation. These materials typically have three diffusion-limiting structural domains: (1) grain interior (2) grain boundaries, and (3) surfaces. Here, we aim to understand diffusion through titania grain boundaries, which are approximated via the amorphous phase. Density functional theory was used to calculate thousands of activation energies of hydrogen hopping. Large-scale amorphous structures were generated using a machine learning force field via molecular dynamics (MD). Kinetic Monte Carlo (KMC) simulations were then performed on the MD-generated structures, allowing us to connect directly with experimental measurements. Using our KMC simulations we can directly calculate the hydrogen diffusion constant, as a function of temperature and stoichiometry, and compare these values with those determined via experiments. This work sets the stage to better understand how temperature and local atomic structure affect properties such as diffusivity, solubility, and permeation.
11:10 AM
Multi-objective Optimization of CALPHAD and Empirical Models to Discover New High-temperature Metallic Glasses: Jerry Howard1; Leslie Mushongera1; Devicharan Chidambaram1; Krista Carlson1; 1University of Nevada, Reno
Metallic glasses (MGs) are an emerging class of materials possessing high corrosion resistance, high strength, and ease of fabrication when compared to their crystalline counterparts. However, most previously studied MGs are not useful in high temperature environments because they undergo the glass transition phenomenon and crystallize below the melting point, leading to loss of beneficial properties provided by the glassy state. In addition, good glass-forming alloys are typically located near regions of low melting temperature, exacerbating further the issue of poor high-temperature performance. We have developed and validated a new tool for the discovery of high-temperature stable MGs known as GenMG. This tool effectively couples empirical predictions of glass forming ability with computational thermodynamics through a multi-objective optimization genetic algorithm. GenMG has the potential to improve the use of MG-based corrosion-resistant coatings and has been designed to be both transferable to any reasonable alloy composition and extensible to multi-component systems.
11:30 AM
Phase Identification and Characterization in a Mo-Si-B-Ti Alloy: Qingshan Dong1; John Perepezko2; Laurence Marks1; 1Northwestern University; 2 University of Wisconsin-Madison
Mo-Si-B alloys are attractive alternatives to Ni-based superalloys to improve energy efficiency of gas turbine systems. Using advanced electron microscopy techniques and density-functional theory (DFT), we identified the phase, crystal structure and chemical distribution of the Mo-Si-B-Ti alloys manufactured with directed energy deposition (DED). Transmission electron microscopy was used to characterization the crystal structure, atom arrangement and alloying element distribution. DFT calculations were performed to understand the results from TEM.